Lower rates of asthma and other health problems are frequently cited as benefits of policies aimed at cutting carbon emissions from sources like power plants and vehicles, because these policies also lead to reductions in other harmful types of air pollution. But just how large are the health benefits of cleaner air in comparison to the costs of reducing carbon emissions?

More and more people are living in our cities. They are great places to live, exciting, good jobs, great night life, but also sometimes congestion and unhealthy air quality. The latter problems are improving, however. Efforts to make cities livable without driving are paying off. Bike lanes, bike sharing, and efforts to reduce auto traffic and congestion are helping to improve the air quality in our cities. The U.S. Environmental Protection Agency (EPA) this week released its Second Integrated Urban Air Toxics Report to Congress - the final of two reports required under the Clean Air Act (CAA) to inform Congress of progress in reducing public health risks from urban air toxics. "This report gives everyone fighting for clean air a lot to be proud of because for more than 40 years we have been protecting Americans – preventing illness and improving our quality of life by cutting air pollution - all while the economy has more than tripled," said EPA Administrator Gina McCarthy. "But we know our work is not done yet. At the core of EPA's mission is the pursuit of environmental justice - striving for clean air, water and healthy land for every American; and we are committed to reducing remaining pollution, especially in low-income neighborhoods."

Fracking is once again in trouble. Scientists have found that what gets pumped into hydrocarbon-rich rock as part of the hydraulic fracture technique to release gas and oil trapped in underground reservoirs may not be entirely healthy. Environmental engineer William Stringfellow and colleagues at Lawrence Berkeley National Laboratory and the University of the Pacific told the American Chemical Society meeting in San Francisco that they scoured databases and reports to compile a list of the chemicals commonly used in fracking.

NASA research has revealed the Earth's atmosphere contains an unexpectedly large amount of an ozone-depleting compound from an unknown source decades after the compound was banned worldwide. Carbon tetrachloride (CCl4), which was once used in applications such as dry cleaning and as a fire-extinguishing agent, was regulated in 1987 under the Montreal Protocol along with other chlorofluorocarbons that destroy ozone and contribute to the ozone hole over Antarctica. Parties to the Montreal Protocol reported zero new CCl4 emissions between 2007-2012.

What do a no-drink order in Toledo and a backlash against factory farming have in common? A lot, as it turns out. Residents of Ohio's fourth-largest city were advised for multiple days earlier this month to refrain from drinking their tap water because it had been contaminated by toxic algae. As residents struggled to deal with their contaminated water supply, the culprit behind the problem became readily apparent: factory farms. The Ohio Agriculture Advisory Council (OAAC) is proposing a regulatory crackdown that could forever change industrial farming practices in this Midwestern state.

Nearly three in 10 surfers admit they knowingly surf during health advisories – nearly the same amount that chooses not to surf during periods of elevated bacteria. About 40 percent of surfers said they were unaware if they had ever surfed during an active health advisory. The data can help public officials better warn surfers of potential health risks, said Anna Harding, co-author of the study and professor in OSU's College of Public Health and Human Sciences. "Beach advisories for bacteria are not having their intended effect of dissuading surfers," Harding said. “The lack of awareness about advisories – and willingness to take risks surfing in water that may be contaminated – suggests the need to educate surfers about behaviors that make them vulnerable to illness."

Marine debris has many impacts on the ocean, wildlife, and coastal communities. A NOAA Marine Debris Program economic study released today shows that it can also have considerable economic costs to residents who use their local beaches. The study found that Orange County, California residents lose millions of dollars each year avoiding littered, local beaches in favor of choosing cleaner beaches that are farther away and may cost more to reach. Reducing marine debris even by 25 percent at beaches in and near Orange County could save residents roughly $32 million during three months in the summer.

A commonly held belief that global warming will diminish oxygen concentrations in the ocean looks like it may not be entirely true. According to new research published in Science magazine, just the opposite is likely the case in the northern Pacific Ocean, with its anoxic zone expected to shrink in coming decades because of climate change. An international team of scientists came to that surprising conclusion after completing a detailed assessment of changes since 1850 in the eastern tropical northern Pacific's oxygen minimum zone (OMZ). An ocean layer beginning typically a few hundred to a thousand meters below the surface, an OMZ is by definition the zone with the lowest oxygen saturation in the water column. OMZs are a consequence of microbial respiration and can be hostile environments for marine life.

The fate of oil during the first day after an accidental oil spill is still poorly understood, with researchers often arriving on the scene only after several days. New findings from a field experiment carried out in the North Sea provide valuable insight The immediate aftermath of an oil spill The fate of oil during the first day after an accidental oil spill is still poorly understood, with researchers often arriving on the scene only after several days. New findings from a field experiment carried out in the North Sea provide valuable insight that could help shape the emergency response in the immediate wake of disasters.

Even when the sea looks clean, its surface can be flecked with tiny fragments of paint and fiberglass. That's the finding from a study that looked for plastic pollution in the uppermost millimeter of ocean. The microscopic fragments come from the decks and hulls of boats, and they could pose a threat to tiny creatures called zooplankton, which are an important part of the marine food web. The discovery is "continuing to open our eyes to how many small synthetic particles are in the environment," says Kara Law, an oceanographer who studies plastic pollution at the Sea Education Association in Woods Hole, Massachusetts, and wasn’t involved in the study.